In the fields related to life sciences such as genetics, immunology, molecular biology, and environmental science, flow cytometry is widely used to analyze microparticulate samples such as living cells, yeast, and bacteria. Particles or cells from 500 nm up to 50 micron can generally be measured in flow cytometry. In general, in the case of analyzing a cell or the like with a flow cytometer, a label made of a fluorescent substance is attached to the surface of a cell to be analyzed. Next, a liquid such as water or saline is used to move the labeled cell through a flow channel of a flow chamber, which is an area in which the labeled cell is to be analyzed, and laser light having a relatively high output is radiated towards a predetermined position to irradiate the cell. Then, forward-scattered light and side-scattered light, which are generated due to the size and structure of each cell, and fluorescence, which is generated by excitation light irradiation, are observed. In the case of observing fluorescence from a cell, a configuration for spectral analysis of the fluorescence condensed in a direction other than an irradiation path of excitation light is widely used to avoid adverse effects of transmitted or scattered excitation light. Fluorescent substances to be attached or combined for each type of cells are known. Accordingly, the wavelength and intensity of the fluorescence are observed and the intensity component to be superimposed is compensated to thereby identify the type of each cell flowing through the flow channel.
Some flow cytometers perform measurement of cells or the like with laser light. A large number of microparticulate samples are supplied to a flow chamber through a tube from a container such as a vial containing the samples. The flow chamber is generally configured to permit microparticulate samples to be aligned and flow by a method called hydrodynamic focusing.
The attached drawings are for purposes of illustration and are not necessarily to scale.